Dell d620 AC Issue: Won't recognize its plugged in.?

I have a Dell 620, it runs like a champ, until a week ago, it doesn't recognize that it is plugged in. From what I hear this is a Mo/bo issue. There is no warranty. My question is this, can i bypass the issue by getting a docking unit. It is no longer plugged in, being that its placed on the serial port on the bottom? I like the computer, and would rather work around the problem than try to tear it apart. It does all I ask of it, including running photo-shop, and illustrator simultaneously, with minimal lag and that could be solved with adding ram.